Understanding varietal responses to varying plant population densities under high moisture and drought conditions of sub-humid West Africa is crucial to developing stress-tolerant, high-yielding maize hybrids steering sustainable development in the Nigerian grain industry. This study evaluated the independent and combined effects of maize varieties, plant population density, and in-situ moisture conservation on growth attributes, yield components, and final grain yield in the Southern Guinea Savanna Zone of Nigeria. A factorial Randomized Complete Block experiment (2 × 2 × 3) comprising two varieties (SAMMAZ 52 and Oba 6), two moisture conservation approaches (mulched with dry maize stover at ~4 t ha?1, and un-mulched control), and three plant densities (22,222; 53,333; 88,888 plants ha?1) was conducted in three replicates over 36 plots. The hybrid (Oba 6) consistently outperformed the open-pollinated (SAMMAZ 52) variety for most growth traits, yield components and final grain yield (5.17 t ha?1), conferring a 35.4 % yield advantage. Medium density (53,333 plants ha?1) enhanced leaf number, stem girth, ear size and kernel number, while mulched plots improved stem thickness, yield components giving a yield advantage of 27.0% relative to un-mulched treatments. Significant variety × density and variety × moisture interactions revealed Oba 6 as more responsive to medium density and mulching, producing optimal performance under mulched, medium density conditions. Positive correlations between grain yield and tasseling time, kernel number, ear length and grain weight further highlight important selection traits for breeding. The study recommends medium plant density combined with organic mulching and hybrid selection as a viable strategy for improving maize productivity under rain-fed Savanna conditions.
grain yield, in-situ moisture conservation, maize, population density, and varieties